Momentary switch



1953 0. M. BOLLHOEFER 2,648,728

MOMENTARY SWITCH Filed Aug. 26,1950

INVENTOR. 52 T 04L: M. BOLLHflE/ik Patented Aug. 11, 1953 MOMENTARY SWITCH iDale M. Bollhoefer, Cedar Rapids, Iowa, assign'or -t-GollinsRadioCompany, Cedar-Rapids, Iowa,

acorporation oflowa iamilication August 26, 1950, S erialN 0. 181,633 6 Claims. (01. 200-6) This invention relates .t'oiswitc'hes and 'in particular to a momentary switch which has a re- :membering i circuit.

. Many -times it is -desirable to know'which direcfticn :a :SWi-ttbh was =last moved from the central neutral :position. For example, in remotely controlling an airplane wherein the'p'osition of the elevator: is'adjusted'by transmitting a signalfrcm the :remote :position, :if the observer is unable to see the aircraft :he 'is'icontrolling, it is practically impossible for:hi'm to remember the last informatiohserit to :the aircraft.

:It is an object'of this invention, ithelefore, to provide -aimomentary switch which hasarremembering circuit connected therein for indicating the. last position to which therswitch was 'moved.

:Anotherxobject'of this invention isto provide a :simple and economical remembering 'switch which will assure recollections of past switch movements.

A feature of this invention is found in the provision ior 'a :fiexible switch which is movable .to momentarily engage one of two contacts to actuate a relay, forexampie; and a second switch that is always :in engagement "with one of two contacts. Thelpositicn of the seconds'witch indicates the last contact made by the momentary switch.

Further objects, features and advantages of this invention will become: apparent'from the 'following=descriptionand claim-s when read in view of the-drawings, in which:

Figure 1 is a top view of the switch of this invention with the cover removed;

Figure 2 is aside-view 'of the switch with cover in place;

Figure 3 is a' sectional view taken'on line 33 of Figure 2 and illustrates thespring biasing unit for :the switch lever; and,

Figure4is aeircuit'diagram of the switch of this invention.

:Referring to Figure 1, a generally rectangular housing which maybe made of Bakelite, for example, is formed with a central opening I'l. Adjaoentoneend-lZof-the housing I 8 are formed a pair of recesses I3 and M which are adapted for receiving therein electrical terminals 16 and I! which extend into the opening l-I. Adjacent the opposite end of the housing are :formed a second pair of slots I8 and I9 which receive therein terminals 2| and 22, respectively.

Intermediate theends "of the member H! are formed'a 'pair orslots 2'3and24. A'pair of-eurved spring straps 26 and 21 are received in the slot 23 and are fastened to a terminal .28. A flexible 2 member '29 is formed with two longitudinal slots and the center "portion, thusformei-has'a small section removed for receiving the curved spring straps 28 and 21. The member 2-9 has'a'ttac hed *at one "end thereof 'an electrical contact 3 l which 'is'movab-le between the terminals [6 and '|'7, a1'1'd has attached to the opposite end an insulating strap 32 to which is "connected ail-electrical contact '33. A flexible metal conductor '34 extends from the contact to a contact 36 mounted in the slot 25.

An insulatin strap 31 is attached to the terminal 36 and forms an insulating shield between the "conductor 34 and the member 29-. A throw arm 38 is pivotally supported by a pin 'fl which passes through an extending threaded portion 41 of theme'mber fl]. The inner e'ncl ofthe arm =33 is formed with a tl 'sh'aped yoke' l2 which is 'engageable with the end of portion32. As is best shown'in Figure 3, throw-arm '38 is spring biased to a central neutral position by'the springs '40 and 45 mounted in the member -4I. Thus, whenfthe switch is release'dit always returns'to a neutral position.

The Width of the yoke '42 is Such that When the throw'ar m 38 i in the centralneutral position, thec'ontact "33 is heldout of engagement 'with-terminals'fl 0r'22. The'lost motion allowed by the yoke allows contact 33 tor'emal'n' closely adjacent to the terminal which it last encounterecL'thus preventing the other contact?! from changing position. 'For'exampl'e, due 'to spring action contact 31 will always be engaged with either terminal [6 orfi. When the contact 33-is movedto engage terminal 2!, the 'contact'?! will flip' over to engage terminal 16. 'When'the'throw arm 38 is released, one arm 43 of the yoke fl will movie contact 33 out of engagement with terminal 2!. The width of the yoke thus prevents the-member '32 from being moved 'past the dead-centerposition, thus causing the contact 3| to change positions. When it is "desired to momentarily connect contacts 33 and"22,"the'throw arm '38 is pivoted upwardly with respect to Fig ure land the'leg ds ofthe yoke forces member' iz past dead-center unti1 the'contact3'3'is engaged by the c'cntact' 22. Asthe member'32 passes dead center the -s'pring' compression in members 26 and 21-causes contact 3I to move "from engagement with terminal IE to engagement with terminal H. 'A's t1'1e throw arm 38 is re1eased once again, 'the-leg- 4 l or the yoke 42 holdsthe memher 3' 2 so that-the' contact 33 is 'out (if engagement with terminal 22 while maintaining it below dead-center.

Figure 4 is a wiring diagram of the switch illustrating how it may be used in a particular circuit. The contact 3! completes a circuit between terminal 28 and terminal it or H. Lights 46 and 41 are connected in series with terminals l6 and il, respectively, and to ground. A battery 48 is connected between ground and terminal 28. The members 26, 2'5 and 29 complete the electrical circuit between contact 3| and terminal 28. Movement of arm 33 momentarily completes a circuit through one of the two relays 49 and E. The relays 49 and 5! may be connected to elevator raising and lowering circuits, respectively, which are actuated when the relays are closed. The contact 33 is electrically connected to terminal 36 by the conductor 34. A battery 52 is connected between terminal 36 and ground. Thus, once the contact 33 has engaged one of the terminals 2! or 22 the corresponding relay is actuated. The arm 38 may be released until it is desired to change the information given to the control circuit. The light which is illuminated reminds the operator to which position he la-st moved contact 33, and thus his next movement may be made with confidence.

This invention has many uses, and the aircraft illustration is used merely for explanatory purposes.

It is to be understood, of course, that although this invention has been described with respect to particular embodiments thereof, it is not to be so limited as changes and modifications may be made therein which are within the full intended scope of the invention, as defined by the appended claims.

I claim:

1. A momentary switch which has a remembering circuit comprising, a body portion formed with a central longitudinal opening, a first pair of terminals mounted adjacent one end of said body, a second pair of terminals mounted adjacent the opposite end, a third pair of terminals mounted intermediate said first and second pair of terminals, a throw arm pivotally supportedby the opposite end of said body member, a flexible member engaged by the inner end of said throw arm and having a first contact movable between the second pair of terminals, a second contact connected to the opposite end of said flexible member and movable between the first pair of terminals, spring compression members attached to one of said third terminals and attached intermediate the ends of said flexible member, said first contact insulated from said flexible member and a conducting member connecting said insulated contact with the other of said intermediate terminals.

2. A switch which has a remembering portion comprising, a flexible centrally supported member formed with electrical contacts adjacent each end, a first pair of terminals engaged by one of said contacts, a second pair of terminals engageable by the other of said contacts, a throw arm pivotally supported adjacent said first pair of terminals and engageable with one end of said flexible member to move it from one to the other of said first pair of terminals, and said throw arm biased to a central position which holds one end of said flexible member out of engagement with the first pair of terminals.

3. A momentary switch which has a remembering circuit comprising, a body portion formed with a central longitudinal opening into which extend a plurality of terminals, a flezdble men ber centrally supported by a first of said terminals, a first contact attached adjacent one end of said flexible member and movable between a first pair of said terminals, an insulating member attached to the opposite end of said flexible member and a second contact mounted thereon and movable between a second pair of terminals, and a pivot arm supported by said body portion with one end having a yoke extending from the inner end thereof that is engageable with said insulating member to move said second contact from one to the other of said second pair of terminals.

4. A momentary switch which has a remembering portion comprising a body member formed with a longitudinal opening therein, a first pair of terminals mounted within said opening adjacent one end thereof, a second pair of terminals mounted adjacent the opposite end thereof, and a third pair of terminals mounted intermediate the ends thereof, spring means'extending from one of said third pair of terminals, a flexible member formed with a pair of longitudinal slots and a transverse slot formed through the central portion of said flexible member and attached to said spring means, a first contact connected to one end of said flexible member and movable between said first pair of terminals, a second contact insulatingly mounted adjacent the opposite end of said flexible member and movable between said second pair of terminals, an arm pivotally supported adjacent one end of said body portion and having an engaging portion of a generally U shape for engaging the opposite end of said flexible member.

5. Apparatus according to claim 4 wherein said arm is spring-biased to a central position and wherein the engaging portion holds said second contact out of engagement with either of said second terminals except for momentary contact while said arm is depressed.

6. A momentary switch in combination with a remembering switch which indicates the last position of the momentary switch comprising, a body portion formed with a generally longitudinal opening therein, a flexible member formed with a pair of longitudinal slots and a transverse slot across the central portion thus formed, spring means engageable with the ends of said central portion within said transverse slot and attached to said body portion, a first contact mounted in one end of said flexible member, a second contact insulatingly mounted in the opposite end of said flexible member, a first pair of terminals mounted a in said body portion adjacent said first contact DALE M. BOLLHOEFER.

References Cited in the file of this patent UNITED STATES PATENTS Name Date Miller May 10, 1949 Charbonneau Oct. 24, 1950 Number 

